莲蓬多酚的提取工艺优化、鉴定及抗氧化活性研究

Optimization Extraction, Purification, Identification and Antioxidant Activity of Polyphenols from Lotus Seedpod

为促进莲蓬多酚资源的利用,对莲蓬多酚的超声辅助溶剂提取工艺进行了响应面优化,并对纯化后的莲蓬多酚(LSPs)进行了组分鉴定和抗氧化活性初探。结果表明,LSPs超声辅助溶剂提取的最佳工艺条件为提取时间43 min、乙醇体积分数40%、料液比1:40 g/mL,此时LSPs的得率可达(8.54±2.98)%,其中料液比对得率的影响最为显著。经AB-8大孔树脂柱层析纯化后得到的LSPs多酚含量达(76.06±2.10)%。LSPs含有多酚类物质紫外、红外光谱的典型特性,液质联用仪分析出5种多酚类物质,组成单元为儿茶素、表儿茶素、没食子儿茶素、表没食子儿茶素和原花青素。LSPs对DPPH·和ABTS;·的清除能力与抗坏血酸和原花青素相近,且其清除能力与LSPs浓度具有良好的量效关系;LSPs对·OH也具有一定的清除能力,但并不存在浓度依赖关系。

In order to promote the utilization of polyphenol resources from lotus seedpod,response surface experiments were employed to optimize the ultrasonic-assisted extraction conditions of polyphenols from lotus seedpod.Then the purified lotus seedpod polyphenols (LSPs) were identified,and its antioxidant activity was preliminary investigated.According to the results,the optimum extraction conditions were as follows:extraction time of 43 min,ethanol volume fraction of 40%,material-to-liquid ratio of 1:40,and the yield of lotus seedpod polyphenols can reach to (8.54±2.98)%.Among all the conditions,the material-to-liquid ratio has the most significant effect on the yield.After purified by AB-8 macroporous resin column chromatography,the polyphenol content of LSPs can reach (76.06±2.10)%.LSPs contained the typical characteristics of polyphenols,and were composed of 5 types of polyphenols.The component units were catechins,epicatechins,gallocatechins,epigallocatechins and procyanidins.The scavenging ability of LSPs on DPPH· and ABTS;· were similar to that of ascorbic acid and proanthocyanidins,and there was a good dose-effect relationship between the scavenging ability and the concentration of LSPs.LSPs also can scavenge the ·OH,but there was no concentration-dependent relationship.